KL Engineering served as the prime design consultant for the STH 93 Tunnel Lighting Improvement Project in Eau Claire, Wisconsin. The project was developed as part of the Wisconsin LED Retrofit Implementation Plan, a statewide initiative in which KL Engineering played a leading role to modernize transportation lighting infrastructure, improve energy efficiency, and reduce long-term maintenance costs. The project involved replacing aging high-pressure sodium luminaires within a 380-foot tunnel with energy-efficient LED technology while maintaining compliance with Illuminating Engineering Society (IES) tunnel lighting criteria. Extensive field investigations, photometric modeling, and existing conditions assessments were performed to optimize lighting performance, improve visibility, and enhance safety for the traveling public.
A key component of the project was evaluating the balance between infrastructure reuse and complete replacement. KL Engineering analyzed multiple alternatives for the existing lighting supports, conduit raceways, controls, and electrical infrastructure while assessing constructability, lifecycle costs, future maintenance requirements, and energy performance. Detailed photometric studies and energy savings analyses were used to compare design options and identify the most effective long-term solution. The resulting design demonstrated how strategic infrastructure investments can improve lighting quality, increase operational efficiency, and maximize return on investment for transportation agencies.
